Carburizing box



April 27 1926. l

E. D. AIKEN CARBURI ZING BOX Filed Jan. 14, 1924 l I 'l P f v JM 1*] flwl ATTORNEY' Patented Apr. Y27, y1926.

UNITED sfrfn'rees'f PATENT; orales; l

EUGENE.V DIX AIKEN,: or EOGHESrEE,Y NEW Yoran. Assreivoamo THE CAEBoX .a oonzeoeafrrorr, or :nocnEsTEE,.NEW YORK..

CARBURIZINGrt BOX.

Aplicato'n filed January 14,1924. VSerial No'. 686,018.'l

To all whom timmy concern:

le it vlrnownthat I, EUoENEUrx/AJKEN, a citizen of the UnitedStates, and a. resident of Rochester, inthe coun-ty of Monroe and State'. of New' York, have invented a 'new and improved Carburizing Box, .of I'which the folloivinglis specification.l

The present `invention relates tio-boxes employed in the cementatlionandcarburizing of steel, anobj ect "of thev inventionbe gto providev abox of this''characterl that Willbe prac-- tically gas-tight.:v

lt is iv-ell known 'that When solid comente are used as the paclnngmaterial Withwhich the boxes arecharged,.and thebones subjected lto carburizing heat, certa-in Carbonaceous grasos are formed and that the transfer of carbon.` from thepaching; material. is accom plishedQchie'fly by these gases. .rilsog the greater the-gas pressure Within the boxes, up to the limit ofv approximately() lbs. per square inch, Whenthe articles being treated have reached the transformation pointer ten'ipcrature at which cementation taires place, the faster penetrationfof carbon into the steel Vis obtained, that is", the time 'necesf sary to obtain apredeterinined depth of case on the articles isjlessened and'betterresults obtained accordingly as the quantity and pressure of lcarburiyiing gases* are-increased- The common 'practice heretofore hasbeen to place a coveroverthe open face of a carburizing4 boX- and depend upon lire-clay, with which the cover is luted tothe side Walls of the box, to form an effective sealagainst the escape'of gas. This methodyhowever, is unsatisfactorv7 for-the reason that the moist ,lay dries and .breaks .olf `wheny subjected/to the intense heat Vof the furnacesy in Which the boxes are placed 'and is -insucientto-Withstand the gaspressure generated Within the boxes. Furthermore, air striking the heated carburizing material causes" the exposed parts thereof to turn to ash.

As an experiment to determine Whenthe carburizing gases begin to form and to What extent they escape before cementation takes place, I charged a box with carburizing'material and sealed it absolutely. gas-tight with the exception of a single" vent to-Which a tube was connected leading `from the furnace in which the boi; was placed. At about 8500 F., gas pressure had formed sufficientlyin the box so that lthe gas begantoburnatthe outletofthe conductorpipe.` At atemperature I of 871,0" F., the flame at fthe pipe-outlet AWas one and onen-half inchesl longv andfgradually increased until 1t measured-A su.: inches 4when,

the temperature had reached 121051" F' carburiaing lgas Will have escaped without! functioning ,informingthecase on the articlesand, also, the solid cementWill havelost considerableof its carbon content, thusvreducing its effectiveness-,as a carburizing agent.

In Vthe construction of 'alcarburizing` `box that `Will be gas-tight orpractically so, Y I do away with the lnecessity of 5 and inconvenience of lut'ing `the cover on th'eboxglthis being another objecttof'the invention, .and a further object is to provide a cover' that may befreadily placedA onandremoved fromthe box andthat lWilllbe held) in position by simple but etfectivelyoperable clamping devices.

A further object of the inventionis tovproa dry material intermediate the'box and'va flanged cover, and so positioned-lrelativeto the two members th at aneffective/sealing of the box is obtainedeveny though thereis a comparatively'loosettingiof the cover.

' A further-object of fthe invention is to prof vvide a. gasketor ysuitable packing medium of vide a box and coverfwith apacking medium interposed between-1 them and' tohemploy Wedges insertable between oneof the-mem'- bers andl overhanging port-ions of lthe vother member as means for drawing thecover and boi;v togetherv and against said packing medium, the Wed-ges also functioning touhold the cover against warping.v

A further object of ithefinvention' is to vprovide'- a boxadaptable, if desired, to` being placedin a furnacebottom sideup;

A furtherobject gof the-invention is to -proc vide means interchangeable'Withthe cover for 'holding `the pack-'ing medium 411i-place, 1n the event thatfsandioryother such 'granular substance is used, when the box is turned bottom side up to discharge the contents.

And, a still further obj ect of the invention is to provide a box of the character described that will be inexpensive to manufacture, that will stand more usage than the ordinary box cast of like metal, and that can be sealed more quickly an'd effectively than one in which a luting materialv is used for attaching the cover.

To these and other ends the invention consists of certain parts and combinations of parts as will be fully set forth in the following description and particularly delined in the appended claims.

The accompanying drawings illustrating the invention are as follows Figure 1 is a top plan view of a rectangular box with a portion of the cover broken away.

, Fig. 2 shows the lower part of the box in end elevation and the upper part in section on the line 2 2, Fig. 1.

Fig. 3 is a sectional detail on the line 3 3, Fig. 1.

Fig. 4 is a perspective view of one of the wedge pieces.

Fig. 5 is a top plan view of a cylindrical box with parts of the cover broken away.

Fig. G is a sectional view of the upper part of the box taken on the line 6 6, Fig. 5.

Fig. 7 is a side view partly broken away of the cover for the box shown in Figs. 5 and 6.

Fig. 8 is a fragmentary side view of the cylindrical box with the cover removed.

Fig. 9 is a top plan view of another mcdiiication of the cylindrical box.

Fig. 10 shows in detail the member interchangeable with the cover for holding the packing medium in place when the box is tipped over to discharge the contents.

Fig. 11 is al sectional detail of the box showing such interchangeable member in position; and, Fig. 12 is a sectional detail on line 12-12, Fig. 9.

Similar reference numerals refer to similar parts throughout the several views.

Referring first to Figs. 1 to 4, inclusive T he box therein shown is rectangular with the numeral 1 representing the bottom, 2 the side walls and 3 the end walls, while a removable cover 4 formed with ay downwardly projecting marginal flange 5 is provided for the open top side. The side and end walls Q, and 3 are increased in thickness at the 'open side of the box and formed therein is an upwardly opening channel or groove G for receiving a gasket or packing 7 of any suitable non-combustible material as sand or asbestos rope and the flange 5 of the cover 4, the channel being somewhat wider than the flange 5 so as to allow the cover being properly positioned even though there might be slight irregularities in alignment of the mating parts, both the box and cover being rough castings and neither having any finished surfaces.

Formed on the side walls 2 of the box are upstanding lugs 8 provided with reinforcing 70 ribs and having inwardly turned lateral projections 9 the under faces 10 of which are preferably slightly inclined in the direction of the length of the box, these projecting portions 9 overhanging the cover 4 so that 75 wedge pieces 11 may be inserted between the cover and projecting box members, in the manner clearly indicated in Figs. 1, 2 and 3, for the purpose of clamping the cover firmly on the box and against the packing me dium in the channel 6. This channel, it will be noticed, being substantially in line with the side and end walls of the box, the pressure due to the wedges being driven home will be exerted directly against these side and end walls. The wedges are preferably made of a metal having a greater expansion under heat than that of the box so that when the boxes are subjected to furnace heat the greater expansion of the wedges will tend to draw the cover and box still more firmly together.

The side walls 2 of the box are provided with longitudinally extending ribs 12 whereby the box may be readily picked up by a. fork or other suitable handling implement, and lugs or pads 13 are formed on the bottom wall so that a space will be provided between the box bottom and the sup porting surface. The box may be placed in a furnace with either the top or bottom uppermost, and in the latter event the projecting portions 9 on the lugs 8 will act as supporting feet.

In Figs. 5 to 8, inclusive, there is shown a cylindrical box 14 having an annular groove 15 for receiving a packing 7 and the annular rim or flange 16 of a circular cover 17. In this instance wedges 11 are also used to hold the cover in place, such wedges engaging the cover and the inclined under faces of the laterally turned over-hanging portions 18 of two oppositely arranged lugs 19 upstanding from the side wall of the box, the inner faces of these lugs being tan- 115 gential to the cover so that the latter may be placed on the box by inserting it under the overhanging lug portions 18.

In the cylindrical box shown in Fig. 9 there are three regularly spaced lug mem- 120 bers 20, 20 and 21, each provided with an inwardly turned lateral projection under which a wedge 11 engages for tightening the cover Q2. Inv this construction of box the lug 21 is removable to permit placing and l2 removing the cover, and to this end any suitable means for detachably holding the lug in place or pivotally mounting it may be employed. A preferred way to removably secure the lug is to have it engage between 130 llO two spaced ears 23" projecting outwardly from the side `of "the boxnand to Lhold yit against upward inovementby 'forming abut'- ments ,24 oiiits inner end'for engaging under e This illustration shows the box as'liavin'g a tubular .core 25; "andthe cover. as having anv openingl daligned with the core; f Also, the boxhas two Aannular. grooves or channels-l 27 `and '28," the channel-Q lbeing inL the-outer wall" and Ltliechannel 28' in `the'wall of "the tubiilar` core, while "co-operating flanges :.29 and 3() for the channelsi27. land"28;"respectively,l dependl 'from' .the cover A22. f

VVhen'fusingthe boxes, tliexarticles .33 lto be case hardened are placed `"therein and einbedded fin 'a suitable:v cement` `or Icarburizing material 34, after'which the covers are placed in position under they overhanging box'projectionsandthe wedges drivenr'v into place .so asitolirmlycompress the gasket o r `packing:mecliuini` In order to remove'the covers, the wedgeszare' driven out, "the Covers raised so that -marginal flanges clear the top edges of the "boxes 'and thenv moved sidewis'e from under the overhanging projections.. i

Ineach instance thek inner wall of the channelfor receiving the sealing'medium preferablyprojects above the 'outer wall so that,in the event a'granularsubstance such as sand is used.the'fsaxne inayjbey brushed out of the channel with less danger of particles thereof falling into the. box. Also, this construction.'permits a` morel ready align-L ment. of the cover.l p e My invention also! contemplates theprovisionofr" means "for holdingthe sealing medium in place,v should aj granularL substance be used, when 'the boxes are turned bottom side pup" to discharge' the contents. Tothis'end, according to the shape of the box, whether `cylindii'calor;rectangular, a template isfrniedto fit within the channel and cover 4suchsubstance.` At 3l, ink Figs. 10 and 11, there is shown such a member adapted 'for use witha box such as'illiistrated in Figs. 1 and 2. This member is interchangeable withthecov r and is held in placebywedges `eirgaging"-unduer the overhanging projections which cpo-operate with the wedges 11 in holding the cover in place.

In fact the wedges ll by placing them edgewiseI may be used for this purpose, and-to this end a side face thereof is also tapered.

From the foregoing it will be seen that I have providedk a` carburizing box employing a non-combustible and preferably dry packing or sealing medium between the box and cover and that suoli packing is so arranged as not to require replacing each time the box is used. Also,rby the use of readily manipulated wedges co-operating with the cover and box so that the cover, which mayr have a comparatively loose fit, is firmly held in place and the box made practically gastight Besidesthisifthe use of lire clayf'or other 'such lut-ing material which has to 1 be.

'applied.finca'fmoist condition is-- eliminated anda'box -.provi.de'd whichiby being practi'- n callyfgas-tight insures better results p and a yconsiderable` saving Aofi time in the `work done.y f

y Although theibox'- is primari-ly intended for carbnrizing,`4- it? niayr also bel used for annealingipurposesias the 'method of 'sealing it iwillV cause :it 5to' functiony equally. welll fin kepiiigjair ont, iis-required when annealing, as preventingfthe escapeof gas fromlwithin.

lVhat I claim is: 1.- In- -a device l of `the character described, abox' v.hz'ivi-ng- Ka channel inf thef-wallr `thereof at thel open side of thefbox,` a cover 1formed with axm'arginalviange adapted Ht'o' be receivedin saidf'channehi'the Isides fof, the cover channehf upsta-nding f and inwardly 'turned projections castiintegrally on opposite sides ofsaid channel outer wall, andrwedgesu'en gaging between thek cover and said-"projec tions-for liol'diiigltlie-coverin place. i

` 2.2.In-a device of thecharacter described,`

a Vbox Alia-ving'a channel in the wall thereof at the open side of# -the box," a' noncombustible.Y packingV or lsealingmedium in saidchannel, a cover-formedwith;a marginal flange terminating ishorty 0f the outer v'wall of lsaid 85 n which restsupoiisaid packing*andwoverf hangsl'thew inner. wall of the.` channel', inwardly turned-lateral projectionscn the walllof l'the box,` andy wedges engagingffbetween the` cover and"said projections `for f drawing .the ^box and "cover together f and holding the cover `in place.VV

Ina device of thecharacter (described. a-box -havinga channel ini-tl'ie-wall thereof at ethewopeii side I oftl'ie` box, a packing or formed with-a :fina'rginal 1 ii-ange whiclriests uponj-said packing xand overhangs the inner l wall of thechannel, A upstandingi lugsv on the walllofffthe ibex; inwardlyl turned'lateral projections on/ said lugs, andl wedges engaging between the Acover i andV said proj ections holding. `the 'cover iii place:

4. In a device of the character described, a box, a surrounding marginal portion of the ies sealiiigifmedium infisaid* channel, a cover y illU wall of which at the open side of the box o wall of which at the open side of the box being increased in thickness and formed with an upwardly opening channel, the inner wall of the channel projecting above the outer wall thereof, a packing or sealing medium in said channel, a cover formed with a marginal flange which rests upon said packing and overha'ngs the inner wall of the channel, upstanding lugs on the wall of the box, inwardly turned lateral projections on said lugs, and wedges engaging between the cover and said projections for drawing the box and cover together and holding the cover in place.

6. A carburizing box or the like having one side open, projections upstanding from the wall of the box, a cover, members carried by said projections extending over the cover, and wedging devices engaging between the cover and said members for drawing the box and cover together and holding the cover in place, said projectionscomprising supporting feet when the box is turned bottom side up.

7. A carburizing box or the like having one side open, projections upstanding and turned inwardly from the wall of the box, a cover, and wedges engaging between the cover and the inturned portions of said projections for drawing the box and cover together and holding the cover in place, said projections comprising supporting feet when the box is turned bottom side up.

8. A carburizing box or the like 'adapted to be placed in a furnace with either its top or bottom uppermost, supporting members on the bottom of the box, upstanding projections on the wall of the box, a cover, and wedges engaging between said projections and the cover for drawing the box and cover together and holding the cover in place, said projections comprising supporting members when the box is placed bottom side up.

9. A carburizing box or the like adapted to be placed in a furnace with either its top or bottom uppermost, supporting members on the bottom of the box, upstanding and inwardly turned projections on the wall of the box, a cover, and wedges engaging betweenthe inturned portions of said projections and said cover for drawing the box and cover together and holding the cover in place, said projections comprising supporting members when the box is placed bottom side up.

10. In a device of the character described, a cylindrical box formed with a tubular core, the outer and inner walls of the box having annular channels therein at the open side ot' the box, a packing medium in said channels, a cover formed with outer and inner ianges adapted to rest upon said packing and be received in said channels, upstanding lugs on a wall of the box, lateral projections on said lugs, and wedges engaging between the cover and said projections for drawing the box and cover together and holding the cover in place.

1l. In a Adevice of the character described, a cylindrical box having an annular channel in the wall thereof at the open side of the box, a packing medium in said channel, a cover formed with a flange adapted to rest upon said packing and be received in said channel, a plurality of upstanding members on said wall, at least one of which is movable from an upstanding operative position, inwardly turned lateral projections on said members, and wedges engaging between the cover and said projections for drawing the box and cover together and holding the cover in place.

l2. In a device of the character described, a box having a surrounding channel in the wall thereof at the open side of the box, a packing medium in said channel, a cover formed with a depending marginal flange which rests upon said packing and overhangs the inner wall of said channel, projections on the wall of the box overhanging the cover, wedges engaging between the cover and said projections for drawing the bo-x and cover together and holding thc cover in place, and a template formed to lit said channel and being interchangeable with said cover.

EUGENE DIX AIKEN. 

